The second problem is constitutional – or parliamentary. At Westminster, Scottish MPs can vote on laws which only affect England – educational reforms, for instance. Sometimes (in the present parliament, for instance) such bills rely on the votes of Scottish MPs to get passed through the house of commons, even when the majority of English MPs is opposed to them. At the same time, English MPs cannot vote on Scottish education or health, because these are devolved matters reserved for Holyrood.

It’s an anomaly, and it’s unfair. But it arises because British devolution schemes are all lopsided. The English do not wish to have their own English parliament, to rank alongside the Scottish, Welsh and Northern Irish legislatures under the higher “federal” authority of a British parliament. There are grounds for this reluctance: the enormous population imbalance between England and the rest of the UK. Such a structure would be “asymmetrical” with a vengeance.

But while the Westminster parliament remains also the British parliament, then it’s an anomaly the English have to put up with. Back in 1886, Gladstone’s great home-rule bill for a devolved Ireland came to grief because so many MPs – including many of his own Liberals – refused to contemplate Irish MPs voting on English matters. The result was a century of rebellion, confrontation and bloodshed.

Now the old arguments resurface, yet again. The problem is being used as a weapon to embarrass Gordon Brown before he succeeds Tony Blair. But there is more to it than party advantage. In 2004, an attempt to circumvent these pressures by granting English regions devolved self-government failed; voters in the northeast (where the proposals were first tested) did not want it.

Since then, talk about creating an English parliament has revived, though still on the margins of politics. The Tories are reluctant to take up the idea, even though an English parliament would almost certainly be Conservative-dominated. Instead, they toy with the idea that Scottish MPs should be barred from voting on purely English legislation. This could have the weird result of a parliament with potentially two majorities: the Conservatives legislating for England, and a Labour government using Scottish and Welsh Labour MPs to impose its will on “British” matters such as defence, foreign policy or immigration. When is a government not a government?

But, in the continued absence of a devolved administration, logic would dictate [although some local parties would object strenuously], at least, a complete redrawing of the membership of all the Westminster-based NI Committees, should the Conservatives gain power and follow-up on this call.. highly speculative I know, and it would also carry the risk of expanding the potential impact of the velvet divorce discussed by Neal Ascherson in his openDemocracy article, which explores the anomalies and, via Barnett, the Scottish subvention.

In a “normal” European country, this could be accommodated in a more decentralised federation (this month’s endorsement of an “autonomy statute” for Catalonia, including recognition of its status as a “nation” and the granting of wider economic powers from the central government in Madrid, is an example). But Britain is not a normal state. Because of the archaic doctrine of parliamentary sovereignty (absolutism), there is no halfway house between devolution and independence. Reluctantly, the Scots may come to feel that independence is the simplest and least quarrelsome way to manage the relationship between Scotland and England – much as the Slovaks did in 1993, when the Czechs grew tired of making further constitutional concessions.

Almost three hundred years after the treaty of union, are we sliding towards a British version of that “velvet divorce”? The only British politician who has enough influence to tackle these problems in the next few years is Gordon Brown, the great Scot at Westminster. He has the intelligence for the task, but does he have the imagination or the courage? There is more at stake here than Brown’s choice of football team.